How to Repair Exterior Mortar or Parging

Learn how to repair exterior mortar or parging. Learn how to apply stucco to an old home where the exterior plaster over stonework is peeling away, and repair the exterior mortar or parging.

LESLIE: Heading over to Wisconsin to chat with Tyler about a foundation problem. Tell us what’s going on.

TYLER: I have an old farmhouse[1] and the foundation[2] walls are actually made of lime and stone and the interior part of the foundation is kind of peeling back and I was wondering what to do to fix that.

TOM: Say it again. It’s the foundation is peeling back?

TYLER: Well, you know how the mortar[3] on the outside – it’s all skin-coated like it was plastered?

TOM: Ah.

LESLIE: Mm-hmm.

TOM: OK. So the parge – that’s called the parging – so the parging …

TYLER: Parging. Correct.

TOM: … is coming off.

TYLER: Correct.

TOM: If it’s already starting to come apart …

TYLER: Yeah.

TOM: … it’s not going to get any better. I would try to get off as much of it as we can …

TYLER: Right.

TOM: … and then you’re going to re-stucco[4] it. And you’re probably going to use an epoxy mix, which is very, very adhesive and is going – it’s going to stick a lot better than what you’ve had before.

TYLER: Just not a regular type of s-border (ph)?

TOM: No, not a regular type of cement. There are definitely stucco[5] mixes that have additives that make them more adhesive and what’s happening to you is you’re probably – whoever did this probably used regular cement and it’s just not working.